10 Biggest Doctor Who 'What Ifs'

10. What If The First Doctor Regenerated In The Celestial Toymaker?

It's no secret that William Hartnell became incredibly difficult to work with during his latter years on Doctor Who. Illness began to become a crux in his performance, toppled with his increase in frustration towards higher management. This reached its heights when John Wiles took over as producer from Verity Lambert. To put it bluntly, the two of them got on like a house on fire.

In fact, it got so bad that John Wiles couldn't even speak directly with William Hartnell. Tensions just kept rising as William Hartnell's difficulty became almost unbearable, making producing the show a headache inducing experience for John Wiles. This made him want to outright get rid of William Hartnell all together. In essence, this was the birth of regeneration. At least as a concept.

John Wiles tried to use Brian Hayles script, The Celestial Toymaker, to write out the star by having him become invisible due to the villain's fantastical powers within his imaginary reality. Upon returning to screen in a physical form William Hartnell was to be replaced by another actor, with the narrative reasoning explained as a by-product of the Celestial Toymaker's games. However, this idea never came to fluwision, forcing John Wiles to leave as producer after his failed attempts to rid William Hartnell from the role.

Things certainly would've been interesting had John Wiles had his way, kicking William Hartnell out the TARDIS five stories prior to his inevitable exit. Plus, regeneration wouldn't have been an established element, nor a reasoning behind The Doctor's sudden change, meaning the longevity of Doctor Who would be left in the air, with future producers being forced to come up with other bizarre scenarios to recast the pivitotal role.